COMFREY

Knitbone, Woundwort, Healherb, Gum Plant, All Heal

Symphytum officinale F. Boraginaceae

Description

Plant origin, Asia and Europe; a perennial growing from a thick, fleshy, brown-skinned root system, that can delve deeply into the sub-soil in search of moisture and minerals. Oblonglanceolate, dark green leaves, 50-120cm long, with long, round-grooved, petiole stems. The whole plant is covered with short hairs that give a rough feel when touched. Flowers form as coiling, terminal racemes in colours of mauve, blue or pink.

Comfrey

As comfrey rarely sets seed, it is generally propagated by division of roots; in fact, each piece of broken root has potential to shoot. Plant in a permanent position, as comfrey can have a very long life. Andrew Hughes, who researched comfrey over many years, said: "Your comfrey will outlive you and still be growing, if you treat it properly". Choose a sun or partial shade site, and loosen heavy, compacted soil. Enrich the soil with compost or a nitrogen rich dressing regularly, and water during dry periods. The more the leaves are picked by cutting or pulling at the base, the more the leaves will keep coming. Regular cutting will stop the plant from flowering so it can put this energy into leaf production. Plants clump thickly and expand but roots do not run, like mint. Do not plant too closely to small herbs, as the large leaves of comfrey may shade them out completely. In temperate climates, comfrey goes deciduous in winter. On the Sunshine Coast, Queensland, we have leaves to pick all through winter.

Comfrey prefers humus-enriched soil (abounding in aerobic bacteria, fungi and micro-elements) to artificial fertilisers. It likes a slightly alkaline soil at pH 7.2 but will also grow well in acid soil. It is only when comfrey roots get down to the subsoil, that the plant is able to draw up minerals from deep down; the plant then reaches its maximum in food value, in vigour of growth and palatability for stock feed. Plants will produce copiously with a plentiful supply of water, but dislike being waterlogged.

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Medicinal Uses

Recorded history tells of comfrey’s use, since ancient times, for healing. Dioscorides, author of one of the oldest herbal texts, ‘Materia Medica’ of 50 AD, prescribed the plant to heal wounds and broken bones. Many writers since have honoured the herb. The name comfrey is believed to come from Latin ‘confera’, meaning knitting together. The genus name symphytum means to heal together, and for this use, it is renown: that it can assist the body to heal any part that is torn or broken, which also explains the reason for another common name, knitbone. Leaves or roots applied as a wash, poultice or ointment are used for bruising, sciatica, boils, rheumatism, neuralgia, varicose veins, bed sores, wounds, ulcers, insect bites, tumours, muscular pain, pulled tendons, gangrene, shingles and dermatological conditions. A local grandmother told me she makes comfrey ointment. So renown is it for healing, that her grandchildren call it Grandma’s magic cream. Adding comfrey to the bath water is said to promote a youthful skin. Comfrey acts as an emollient and is very soothing, inhibiting further damage to tissues, stimulating the production of cartilage, tendons and muscles. It has been esteemed as a blood, bone and flesh builder. The dark green colour of the leaves indicates the richness of chlorophyll with a molecular structure closely resembling our blood. Chlorophyll acts as a catalyst, to promote healing within the body of man and animals, and is a valuable blood purifier. Scientific research shows that chlorophyll helps to rejuvenate old cells and promote the growth of new cells. This action, together with comfrey’s allantoin properties (a cell proliferant) provides us with a very powerful herb. Allantoin is one of the elements that makes comfrey unique. Allantoin is also produced in the allantois gland of the umbilical cord (the link between mother and developing baby, which feeds the embryo) for promoting rapid cell growth. Mothers’ milk is also rich in allantoin (which stimulates rapid growth of the new baby) and then the element fades out. This process also takes place in other mammals. Allantoin is a leucocytosis promoter (increases white blood cells) that helps to establish immunity from many infectious conditions.

Comfrey was one of the most popular and widely used herbs of the last two centuries; people had faith in the plant, used it, and experienced miraculous healing. It was held in such high esteem that it was believed that even wearing or carrying comfrey could guard and protect a person on a journey. In my bookshelf, I have more books on comfrey than any other individual herb.

H.E. Kirschner, M.D., in his book, ‘Natures Healing Grasses’, devotes four chapters to comfrey and says, "A leaf a day keeps illness away". In his practice, he witnessed healing of obstinate ulcers, malignant growths and many other ailments. He tells the incidence of a man in New Zealand who casually nibbled a comfrey leaf when walking in a friend’s garden (he had suffered with asthma for thirty years). That night he had unbroken sleep, and when wondering why, thought it could have been the comfrey leaf he chewed, that gave him relief from asthma. So he kept up eating a comfrey leaf a day, and has not suffered with asthma since. He shared this folk remedy with many people who suffered with asthma, who likewise experienced relief by using the routine of leafnibbling. Over the years I have met many people who attribute miraculous virtues to comfrey, and shared their personal experiences.

The healing benefits of comfrey have been spread by word of mouth, in many testimonials. There is no doubt that the plant is very much loved and revered.

However, there is a major problem: Comfrey for internal use was prohibited in Australia by legislation, which placed it on the Poisons Schedule. Why did comfrey fall to such a fate? This decree was made, in 1984, by the Poisons Advisory Bureau, through the National Health and Medical Research Council (NH & MRC). The Council listed comfrey as a dangerous poison, only to be available through pharmacists, by doctor’s prescription. This decision, from NH & MRC, came after sensational headlines in Australian newspapers, in 1978. The headlines caught the attention of readers, causing fear to the public, as well as shock and dismay to people who use comfrey, regularly. I have a collection of press headlines, which would scare people away from the use of comfrey, ever again … ‘Liver damage can be done by herbs.’ (This could mean any herb or all herbs.) ‘Popular Herb is a Killer.’ (Positive enough proof that people have dropped dead from eating it?) ‘Scientist Warns Herb is a Killer’; … ‘ Health Drink Causes Cancer, says CSIRO expert’; … ‘Comfrey is a Killer’; … ‘Be Careful With Herbs They Can Kill You’.

One of the news items reads: ‘Dr. Culvenor’s research group at Parkville has been studying the compounds called pyrrolizidine alkaloids, which occur in such pasture weeds as Ragwort, Paterson’s Curse and Heliotrope, the last two weeds being from the same family as comfrey. At least four of these alkaloids are known to be carcinogens, and it is possible that the type found in comfrey is also carcinogenic, Dr. Culvenor said’. Sounds slightly different than the ‘sensationalist’ newspaper headlines, doesn’t it?

Yes, scientific investigations from various sources have revealed the presence of pyrrolizidine (PA’s) in comfrey, substances that are regarded as potentially hepatoxic, carcinogenic, and mutagenic. PA’s are believed to have an accumulative effect in the body and may cause hepatic vein blockage and liver toxicity. It is said that the PA’s are only converted to toxic metabolites, in the body, by the liver enzymes. When comfrey is applied externally to the skin, as a cream, it is not considered to be a significant intake of PA’s, in view of low dermal absorption of the PA’s. When comfrey is dried, enzymes are released and much of the alkaloid is destroyed.

From trials, in Minnesota U.S.A. in 1987, in an attempt to determine cultural and environmental factors associated with the production of PA’s, it was found that comfrey, harvested at different times in the growing season, can be of varying PA amounts. Roots were found to have the highest concentration of PA’s, generally with 10 times as much as young leaves. In one trial, in 1986, immature leaves contained 0.026% pyrrolizidine, on a dry weight basis. A subsequent harvest during the growing season, had no detectable PA’s in the leaf (the minimum detectable quantity was 5 ppm). The data indicated, harvest time was a critical factor in producing PA free comfrey, and that mature leaves have an even lower alkaloid content, than young leaves.

Outbreaks of PA poisoning in humans, in the past, have usually been the result of accidental contamination of food crops, with the toxic seeds of other plants. One such instance was an outbreak of veno-occlusive disease in Afghanistan in 1974. This outbreak followed a severe drought and the people were suffering from acute malnutrition (an important factor). About 22% of the people showed evidence of liver disease when examined in 1975. The cause of the outbreak was traced to bread, contaminated by heliotropium seed (which grew extensively in the wheat fields). Samples of the wheat examined, were found to contain an average of 40 seeds (300 mg) per kg of wheat.

Cases of liver damage, due to people drinking bush teas of seneca and crotalaria, have been reported from a number of places. J. A. Pembery, B.Sc., advisor to the Henry Doubleday Research Association, Essex, U.K. says, in the book ‘The Safety of Comfrey’, that there appear to be no cases, in medical history or veterinary records, of humans or animals, showing clinical symptoms, of pyrrolizidine alkaloid poisoning, from the consumption of comfrey. Lawrence D. Hills, in his forward in the book, mentions that the Commonwealth Bureau of Animal Health very kindly carried out a computer search through their records of 137,000 cases of stock poisoning by plants, since 1972, and found only one concerning case: a case of comfrey-nitrate poisoning in pigs from excessive use of fertilisers in Germany.

There are two studies, which superficially perhaps, devalues comfrey as a medicine.

STUDY 1: ‘Carcinogenic activity of symphytum officinale’ by Hirono, Mori and Hago, Japan. Comfrey leaves and roots were ground and added to the basal diet of 4-6 week old rats. At various time periods, the rats were killed and examined for tumours. The maximum time of administration of the diet was 600 days, which represented a very large proportion of the life of laboratory rats, (as survival studies on lab rats fed on various diets indicate that only 80% of rats would survive 60 days). Note, the control group of rats in this study received the basal diet without comfrey, but unfortunately comparative survival of these rats was not reported, and much of the data of the whole experiment was inadequate and incomplete. After six months some of the rats developed tumours. Of note, out of 28 rats fed 8% of diet as dry weight comfrey, only one showed a liver tumour at 600 days. STUDY 2: ‘The Structure and toxicity of the alkaloids of Russian comfrey (S. x uplandicum) a medicinal herb and item of human diet’ by Dr. C. Culvenor, et al, Australia, 1980. Although Culvenor and his associates identified eight alkaloids in comfrey, four being new to science; there does seem to be inaccuracy, in quoting results of Pederson (1975 Arch. Pharm. Chem. Sc. Ed. 3.55-64). Quotes indicated that he found a 9% concentration of alkaloids in leaves, when Pederson’s actual figures were 0.9 parts per thousand when estimated by titration, and 1.9 parts per thousand when estimated gravimetrically.

The second part of the research paper deals with trials done, injecting alkaloids into the peritoneal cavity of baby rats. It can be questioned whether using young, developing rats at two weeks of age (when they would be more vulnerable to liver damage than adult rats) could significantly affect the results. Can the results of a baby rat test case, where they were fed extremely high doses by injection, have relevance to the effect of adult humans using comfrey? Noting that one comfrey leaf contains approximately one milligram of alkaloid in this particular test project, it is possible to give a similar dose level for man. As an average man is about 70kg it would be necessary to use the alkaloids from 19,880 leaves to produce a comparative dose level, and possible toxicity. As rat deaths occurred at levels equivalent to comfrey 28 times their body weight, it has been estimated that a man would need to consume 19,880 leaves, for a possible, similar effect. If humans were as vulnerable as baby rats to liver damage; and if these figures were less speculative, then it could be calculated that it would take 16 years to accumulate sufficient alkaloids to produce any detectable change in liver function. This would require eating, approximately, 100g of comfrey leaf, every day, based on each large leaf measuring an average 60cm, which would make 5- 6 large leaves, a day. Therefore, in order to reach the dose level at which the test showed that change in liver function occurred; it would take a man 48 years. Liver damage would result at around 150 years. Note, that these figures, used by Pembery, in: ‘The Safety of Comfrey’, are only approximates, based on the very limited amount of research reported in the rat trials. Pembery states that, with the very low concentration of alkaloids found in comfrey, the chances of accumulating sufficient to cause significant liver damage, are very remote.

Andrew Hughes, in his most informative book, ‘Comfrey, nature’s healing herb and health food’, printed in 1991, says, "The safety of comfrey has been proved by thousands of people, who, like myself, have taken comfrey regularly, on a daily basis. There is no known case of the ingestion of comfrey leaves causing hepatic illness, in either man or beast. If the warnings, given by Dr. Culvenor of the CSIRO, were to be taken at face value there would have been hundreds, even thousands, of victims of hepatic poisoning amongst comfrey eaters, both human and farm animal. My bi-monthly, regular check-up at the clinic, has given me a clean sheet of good physical condition  blood analysis, blood pressure, chest, bowels, etc., and I engage in both physical and mental activities every day". Andrew shares in his book how he and his wife Tomoko, have been taking comfrey in tablet form, for 28 years, amounts from 85 to 135 grams daily. At age 89 (when most senior citizens are retired) he was working fulltime, working in his garden and walking, for an hour or more, daily. Although Australian by birth, his work took him internationally and he lived for 33 years in Japan (before returning to Victoria). I had the opportunity to speak to him, numerous times, by telephone and came to appreciate the extensive research and knowledge he had on comfrey. Andrew’s first knowledge of comfrey came in 1956, from Foster Savage: a great advocate of the herb in agriculture, who at that time was farming in Victoria. Once Andrew settled in Japan, he arranged, with the Japanese Department of Agriculture, to import 50 plants from Foster Savage. This was the beginning of a ‘great adventure’, with comfrey, in Japan: with extensive trials, testing, and interest, by the Japanese Government. When Andrew went to Japan, in 1957, he had little thought that comfrey was to become a matter of major importance to Japanese agriculture. He did not plan it that way, but circumstances provided the opportunity. He was invited to speak to farmers, schools and research groups. Farmers quickly realised the value of comfrey, for it added, enormously, to productivity. Andrew was interviewed by the Yomiuri Shimbum daily press, who saw the potential of comfrey and with a vision, planted up a vast park-playgroundgolf course they owned, on the borders of Tokyo. Once established, they gave away over 1,000,000 comfrey offsets (root divisions) to schools, agricultural co-operatives and private people, who wanted to grow and test the plant. That was just the beginning of the comfrey boom in Japan, and also the beginning of the realisation that the plant could also contribute to human health. Comfrey was not only fed in large quantities to animals producing high-quality table meat, but it was also incorporated into many items of cuisine. Andrew was grateful to the U.K. Henry Doubleday research that had many years of documented information, freely available, that showed data of high concentrations that could be fed to animals (some were 50-80% of daily fodder). He also found that extensive documented research was available, on comfrey in human diet, as a health-promoting tea, green drinks, leaf vegetable, dry leaf flour, as well as uses for reversing many ailments. Comfrey had been esteemed as a blood purifier and healer. Trials undertaken by Henry Doubleday Association members, also showed that it is a valuable plant for pain relief. I have reports submitted by Dr. S. J. L. Mount, Berkshire, U.K., who supervised the trials in 1983, testing 90 members with osteoarthritis and rheumatoid arthritis. Members took comfrey, as either 4 cups of tea or 9 tablets, daily. Dr. Mount reported there were no side effects from this dosage, whatsoever, and no reports of any symptoms, which could be construed as liver syptomatology. Patients reported improvement in well-being, with 23-35% pain relief and mobility.

Another report, is of trials by Dr. Clare Anderson, from the Laboratory of Pharmakinetics and Toxicology, School of Medicine, University College, London, with testing forty long-term comfrey consumers, who then submitted for liver function tests. All were found to have perfectly fit livers! One of these was Emsie du Plessis, who I came to know, by letter and ‘phone. She had eaten quantities of raw comfrey, since 1960. Her story, she wrote at 78 years of age. "A few years ago, I felt a little below par, not really sick, but not my usual self. I was watering the garden on a hot day and I felt dizzy. So I thought, ‘This is it  the beginning of the end, for an oldie like me’. I went to the doctor and he examined me and found that I was a bit anemic and that I should go to the hospital for a full blood test. On the way home, I decided to postpone my visit to the hospital for 3-4 weeks, and to step up my comfrey eating, to 3-4 leaves, every day. When I returned to my doctor, he said, ‘Come in  this is a social call, your blood is perfect’. If the alkaloid damaged my liver, during that time, then I would like to think that allantoin is one of the world’s most powerful, natural healers." I am grateful to Emsie for giving me numerous books and research information on comfrey, from the HDRA.

Another Australian, who valued the HDRA research, was Foster Savage, who I mentioned earlier. I had the opportunity to know him, personally, when he settled in Nambour to farm (and later Cooroy); and, I knew you would guess, he grew lots of comfrey! Wilted comfrey was fed to his animals in large amounts. Why did he allow it to wilt? He told me that animals could eat much more, each day, when it was wilted! He often had groups and private people visit and he would, freely, share his knowledge of comfrey and how it benefited his land, animals and his family (note, he had 13 children). When legislation placed comfrey on the poisons schedule in Australia, and newspapers highlighted the ban, he wrote a letter to the Sunshine Coast Daily, in defense of comfrey, saying:

"I was perhaps responsible for 95% of the comfrey in Australia, having introduced the plant to this country in 1954, and having used the plant in great quantities, since then; I am, perhaps, competent to speak about it and to make a few comments on the …remarks about comfrey made by the CSIRO scientist …"To say that two leaves, eaten daily - over a couple of years - will cause serious disease, is simply not true. In our house, we have eaten 70 leaves, or thereabouts, daily, for 24 years: in the form of comfrey tea, liquidised in a vitamiser as a green drink, and in salads. I also fed comfrey to my farm animals. Knowing the power of comfrey to restore a worn out animal quickly, and make her milk again, I once bought an old cow at the Dandenong Market, when farming in Victoria. It had been discarded by some farmer, as worn out. I put her on comfrey, giving her 90 lbs of wilted comfrey (wilted to increase the cow’s intake of comfrey’s extraordinary nutrients), and 90 lbs made a pretty big heap, about 4 feet high. This poor, old, creature took to the comfrey, without hesitation … she was starving for minerals and her instincts gave her a craving for comfrey. When she began to eat, she would eat off the heap of leaves for a couple of hours, then sit down for an hour or so. Later, she would continue eating, until every leaf was gone. If Dr. Culvenor’s words were true, imagine the poison she would be taking into her body, with this quantity of comfrey daily. If comfrey attacked the liver, then this cow would have died, because she was in a worn out condition. Instead, she doubled her milk output, within a week, and in a fortnight, trebled it. The remarkable thing, was that the cream that settled overnight, was some 3/4 inch thick and the separation of cream from the milk was so perfect, that the cream could be lifted off, with none remaining. I fed comfrey to calves, as much as they could eat, again with only gratifying results. I fed pigs, entirely on comfrey and grain, as much comfrey as they could eat, and the quality of those pigs was legendary, in the district. The fame of comfrey spread far and wide, for my farm was visited by 6,000 farmers from around Australia and from overseas. Finally, I well remember the enthusiastic remarks of the butcher who regularly killed our comfrey-fed calves. He told us that he had never before, seen such healthy livers … that, mind you, after being reared on a herb that was supposed to cause liver diseases!"

It is evident that there are many others, besides Andrew Hughes, who consider the legislation, which restricted comfrey, to be quite outrageous. Classified in the Poisons Schedule defining comfrey as a substance or preparation, which is of such extreme danger to life, as to warrant limitation of its distribution to qualified persons (registered doctors), and which requires special precautions in manufacture or use. Natural health practitioners and the public, wrote thousands of letters of protest and signed petitions, asking Members of Parliament to remove comfrey from the Poisons Schedule and make it available to the public again, without prescription. They were told that they would have to prove the safety and efficacy of comfrey, if they wanted to use it. They were also told that they could submit all the evidence they wished, but the decision would not be changed.

It seems to me, and thousands of comfrey users, that the plant has a proven record going back 2,000 years. Unfortunately, within a book of this size, space is limited to give more detail of data and case histories.

There is also outstanding research to consider, of Dr. MacAllister at Liverpool University Hospital, specifically dealing with the allantoic acid of comfrey, leaf and root as a therapeutic agent. Dr. MacAllister began his studies of comfrey, due to a report in the British medical journal: The Lancet that gave details of comfrey being used as successful treatment for cancer. Many researchers feel, that it is the balance of constituents that operate in a synergistic manner, (working together to balance the action of separate constituents) that makes comfrey so valuable as a healing herb … a balance of allantoin, alkaloids, chlorophyll, mucin, saponins, inulin and an array of nutrients.

After the restriction of comfrey, I rang my local Member of Parliament, asking for available research showing comfrey as being a toxic substance, that it should be listed, and restricted, with deadly poisons. I was sent over 350 pages on pyrrolizidine alkaloids, with a World Health Organisation insignia, dated 1988. However, the information contained very little that was relative to comfrey, but mainly of other species of plants that contained other alkaloids. Over 200 PA’s, are found in plants, mainly in the Asteraceae, Boraginaceae, and Fabaceae families. The most acutely toxic PA’s, are in plants of the senecio and crotalaria genus. The kind of PA’s found in comfrey are generally considered to be less toxic, however, they must still be regarded as having the potential for liver damage, at even low levels. Some comfrey users prefer to use homeopathic preparations as an acceptable alternative to the whole plant, since the poison scheduling of comfrey.

Comfrey Cream

To make an ointment to use externally, take 1 cup of finely cut comfrey root and simmer in 1 cup of olive oil until it starts to soften. Cool and strain. Add 50g of beeswax (usually available from supermarkets). Jasmine or orange blossoms may be added to the simmering mixture, to give the cream a pleasant smell. The cream is used to relieve pain and aid healing of cuts, bites, sprains, arthritis, dry vaginal conditions, inflammation and neuralgia.

Culinary Uses

Over the years many people have asked me: "Do you eat comfrey?" No doubt they want to find out what I think of the legislation, of comfrey, and if it is safe for them to eat. My reply is … when I rang the Queensland Health Department for more information on comfrey, and to see if any other plants had been banned, I was amazed to find that borage together with 25 other plants had been listed as Appendix ‘C’ and ‘of such danger to health as to warrant prohibition of sale and use’. I said to the departmental officer, "But borage is served in restaurants". He said, "This legislation restricts its use therapeutically, however you can still eat it as a food" !!! So, the 27 plants that are considered ‘such a danger to health’ can still be sold and eaten, as a food! We need to ask if our government is really interested in the health of citizens, or are they more interested in listening to the lobbyists behind the scenes. It has been said, that there has been a concerted attack on the concept of health through balanced food and natural herbs, orchestrated by sectors of several professions and some companies that market pharmaceuticals. They don’t like comfrey, since it can heal. They prefer to have people use the thousands of formulated drugs on the market. We know, and they know, many of these drugs have caused side effects and killed many people. Some of these drugs have since been banned and some are still allowed to be used, even after evidence of associated deaths. Also, many food additives are still allowed to be used after thousands of recorded side effects and deaths. Quite a number of substances have produced similar figures which comfrey did in experiments (e.g. saccharin, cyclamates, aspirin), yet there is no evidence that comfrey has poisoned anyone. The suggestion that plants of the same family as comfrey have caused poisonings in Afghanistan, means nothing less than that any plant, vegetable, or fruit which belongs to a family in which there are poisonous plants should be regarded with the greatest suspicion. This would mean, that we could hardly eat anything at all. Lawrence D. Hills wrote in 1985, ‘If comfrey is to be put in the same category as arsenic, you need the evidence that it has killed people. The evidence quoted was in 70 references, relating to pyrrolizidine alkaloids, which is like banning potatoes because they contain alkaloids of the same group as the ones in Deadly Nightshade (Atropa bella-donna). If there is supporting evidence that comfrey is all that dangerous, then this information should be published in the scientific publications of the world. If there is no evidence, they should explain why they are conducting a vendetta against a well known herb, which is more famous for its medicinal value than any other herb sold by herbalists. My concern is that people will be scared of using comfrey, which is a safe and simple answer in some cases of arthritis, and turn to one of the many, recently banned, anti-arthritis drugs, which have already amassed a very considerable death toll in a number of countries’. How has comfrey been used as a food? Many herb lovers use comfrey leaves as a vegetable, like spinach, in salads or cooked. As the leaves are rather rough and hairy, it is best to chop the leaves finely, when adding to a tossed salad or tucked in a sandwich. Some comfrey connoisseurs eat the leaves with lemon juice, because the lemon is said to release the comfrey’s calcium. Use leaves as wraps, to make rolls of savoury rice or mince, baked in the oven, and served with a sauce or gravy. Add leaves to stews, soups, casseroles and stuffings. As comfrey is a high protein (22-36%) that also contains vitamin B12, leaves can be a valuable addition to a vegetarian diet, as there are not many plant sources of B12. The discovery of vitamin B12 in comfrey, in 1959, by Mr. F.N. Turner, M.B.N.O.A., N.N.I.M.H., N.D.D., N.D.A. (who was consultant to the Society of Medical Herbalists, U.K.) was in the course of his work with research of dried comfrey, in the manufacture of tablets: to be used by the association in its medical work, for the relief of asthma and bronchial complaints. The vitamin B12 content, was confirmed by Dr.A.H. Ward of Ayrsome Laboratories, Grange over-Sands, U.K., who analysed from 3.1 to 11.6 millimicrogrammes per gram (varying readings depending on varieties and trial plots from which the samples were taken). Comfrey is a rich source of the amino acid methionine, which has been found to assist the body eliminate cholesterol and reduce fatty tissue and blood pressure.

Comfrey fritters can make an economical, nutritious and quick meal. Make a batter, with egg, milk and flour, and add finely chopped comfrey leaves (omit the thick stem as it takes longer to cook). Season with salt and pepper and, if desired, onions, garlic or other herbs, to flavour. Place tablespoonfull amounts in an oiled fry pan and brown both sides. Serve fritters hot or cold for packed lunches, etc. Whole leaves can be dipped in batter and fried. A woman from Brisbane called at the farm, and shared that, when they were very poor she fed her family on ‘comfrey fish’, the leaves dipped in batter and fried. It was very delicious, she said, and added that, during their time of poverty, they were always healthy! When dipping leaves in batter, if the batter seems to coat the leaves too thickly, dip the leaves in cold water before dipping in the batter.

Juice comfrey leaves with carrots, celery and other vegetables or greens. Make a comfrey smoothie; using leaves blended with pineapple juice, orange or mango. In summer, blend comfrey leaves, zucchini, avocado and carrot juice, to make a refreshing, cold soup. Comfrey used as a vegetable soup daily, has helped to relax and promote sleep for people with nervous conditions. Leaves dried and crumbled, or ground to a green flour, can be added to bread, gravy, soups, and rissoles. Dried leaves are used as a tea, sometimes used with an equal amount of China tea and sugar and milk. Combining comfrey with mint and honey, to sweeten, makes a refreshing tea combination.

In his informative book, on the wonderful attributes of comfrey, Andrew Hughes says, "Comfrey is a food". Hughes points out how medicines may have an immediate effect, the results of which may be felt almost instantly, however the effect does not last. Comfrey, on the other hand, does not act this way. Comfrey is a food, and as such, must be metabolized, like all other foods. Hughes continually stresses this point, explaining that to get the benefits of comfrey, it must be taken regularly and consistently. The effect of comfrey is longer lasting because it is built into the very cells of the body. It should be used, regularly, as a food, because it penetrates to every part of the body and brain, improving both the structure and function of each part. Comfrey contains the same structural material of which the human body is built, the proteins and minerals, plus the catalysts that enable the metabolism to operate more efficiently  vitamins, enzymes, etc. Secondly, its two unique elements, vitamin B12 and allantoin act directly on the blood stream - B12 to create red corpuscles and allantoin to regulate cell formation and increase white corpuscles. Once the blood is affected by ingesting this food, the whole body benefits, even to the tiniest hair, the most remote cell, the tips of the nails, the cells of the brain, the marrow of the bones. According to Hughes, every part of the body functions better as a result of regular consumption of comfrey, and the body as a whole, is more resistant to the attacks of disease and ageing.